Car A/C advice needed

[dud]

Hello all,

I was just checking out my A/C on my '93 SC400 (with R12) and came up with the following numbers:

Temp at vent = 58 degrees

Low-side refrigerant pressure = 30 PSI


It's getting hot here in Florida and I would like to confirm that the system is working at near it's optimal level. Anyone with a manual with the recommended numbers for an R12-based system (or any experience with auto A/C systems) ... do these numbers jive or is more refrigerant needed?

 

[Billb2]

You'll find that R12 is extremely expensive.

Better to convert to R134.

If I remember correctly, R12 vent temp should be 40°f below ambient. R134 will be a few degrees higher.